A couple other notes:
- I tested both the old "Spirit" brand caps and the new Spragues with my (new) capacitance meter-- the old ones had considerable variation in capacitance, wheras the Spragues were all within .003 uF of each other.
- The amp not only seems to have a more solid foundation now, it somehow sounds like it has wider bandwidth. I get the feeling I am not missing anything anymore. I am listening to Leonard Cohen and it is just amazing me all over again. Every single instrument has its place, without feeling crowded.
- I tested both the old "Spirit" brand caps and the new Spragues with my (new) capacitance meter-- the old ones had considerable variation in capacitance, wheras the Spragues were all within .003 uF of each other.
- The amp not only seems to have a more solid foundation now, it somehow sounds like it has wider bandwidth. I get the feeling I am not missing anything anymore. I am listening to Leonard Cohen and it is just amazing me all over again. Every single instrument has its place, without feeling crowded.
Of course.
Seller has about 24 hours to reply (has never communicated) before I escalate from dispute to claim.
Thanks. I agree the orange drops look pretty good in there.
I have considered a choke, however I have no idea of what specifications would be ideal for my amp...
Rethinking my conclusions!
Something happened yesterday that has me second-guessing my conclusions in this thread.
As some of you may know, I've been working on building my own hybrid integrated amp for my bedroom system. I used to have a Lepai 2020 in there and I liked it, but then I started modding it and started to really love it. I decided to start from scratch with a new Tipath TA-2020 amp board and a small tube pre-amp kit...
Well, I've finally received all the parts needed for my hybrid amp, and yesterday after work I threw it all together for a test listen. The chassis/tray is the bottom portion of a Philips DVD player that I gutted. I retrofitted some speaker terminals, inputs, and power receptacle.
I plan to make a front bezel out of wood and then mount a power switch, LED and the volume pot in the front bezel. Then I'll cut a hole in the cover panel for the tube to stick through, and mount the 12vac transformer and the huge capacitor on top a la "retro DIY tube amp" style. Mods to the Tripath amp board include 1) replaced input electrolytic coupling caps with bipolar PIO Roedersteins, 2) removed unnecessary connectors to make room for direct soldering, and 3) (obvious) removed the stock 3300uF power cap and tied in the huge 9500uF sucker! Oh, and I stuck a Russian 6NP3 in the pre-amp, as I heard the stock Chinese tube is garbage.
It sounds un-f&*$ing-believable! Way better than it has any right to sound, that is for sure. I have maybe $60 into this thing (I had some of the parts laying around) and it rivals the Shuguang I-25 it is sitting on, all the while using a tiny fraction of the power of the tube amp! No problem at all driving the Pensil 10.2s to "louder than she likes" levels.
I can't believe it. I listened to it all evening and never once did I get the urge to switch back to the tube amp. Part of me didn't want to admit it, and another part of me suspected that I might even like the DIY "Cobble-Amp" better... I'll wait till this evening to find out if that is the case.
It sounds good enough that I might even use it in the main system as a "summer amp" (so as to avoid roasting my family and I with the tube amp).
"This is no Lepai"
Something happened yesterday that has me second-guessing my conclusions in this thread.
As some of you may know, I've been working on building my own hybrid integrated amp for my bedroom system. I used to have a Lepai 2020 in there and I liked it, but then I started modding it and started to really love it. I decided to start from scratch with a new Tipath TA-2020 amp board and a small tube pre-amp kit...
Well, I've finally received all the parts needed for my hybrid amp, and yesterday after work I threw it all together for a test listen. The chassis/tray is the bottom portion of a Philips DVD player that I gutted. I retrofitted some speaker terminals, inputs, and power receptacle.
I plan to make a front bezel out of wood and then mount a power switch, LED and the volume pot in the front bezel. Then I'll cut a hole in the cover panel for the tube to stick through, and mount the 12vac transformer and the huge capacitor on top a la "retro DIY tube amp" style. Mods to the Tripath amp board include 1) replaced input electrolytic coupling caps with bipolar PIO Roedersteins, 2) removed unnecessary connectors to make room for direct soldering, and 3) (obvious) removed the stock 3300uF power cap and tied in the huge 9500uF sucker! Oh, and I stuck a Russian 6NP3 in the pre-amp, as I heard the stock Chinese tube is garbage.
It sounds un-f&*$ing-believable! Way better than it has any right to sound, that is for sure. I have maybe $60 into this thing (I had some of the parts laying around) and it rivals the Shuguang I-25 it is sitting on, all the while using a tiny fraction of the power of the tube amp! No problem at all driving the Pensil 10.2s to "louder than she likes" levels.
I can't believe it. I listened to it all evening and never once did I get the urge to switch back to the tube amp. Part of me didn't want to admit it, and another part of me suspected that I might even like the DIY "Cobble-Amp" better... I'll wait till this evening to find out if that is the case.
It sounds good enough that I might even use it in the main system as a "summer amp" (so as to avoid roasting my family and I with the tube amp).
"This is no Lepai"
An externally hosted image should be here but it was not working when we last tested it.
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Cogitech,
Nice work there! Looks like a lot of fun. I wish I could hear it in person!
I am not surprised that this systems rivals your nice tube amp - you do have a tube pre-amp to give it the "tube flavor". Have you tried it without the tube pre-amp? I don't know if you have seen my foam core class-D amp using the new Texas Instruments TPA3118D2 chip (30 watts/ch at 0.1% THD from a 4 mm x 11 mm x 1 mm high IC) but it sounds amazing compared to my stock Lepai. It even sounds better than my old Yamaha RX360 that I have put that away to make the new amp my main system amp. It will be the main one until I finish the sibling chip - the TPA3116D2 on a PCB (50 watts/ch - same form factor). The depth of the bass and clarity of the highs and how free and open it sounds is what really did it for me. More info on this amp is here in this thread: http://www.diyaudio.com/forums/class-d/219730-tpa3118d2-13.html#post3427618
I don't know if you have heard of LDR's - passive light sensitive resistors that let you control volume without any moving pots or active components to add noise. You might want to look into it for ultimate sonic purity. It will be cleaner than a tube preamp and has no amplification, but that is OK if you intend to run it between your CD player and your TA2020. http://www.diyaudio.com/forums/analog-line-level/80194-lightspeed-attenuator-new-passive-preamp.html
Here is a pic of my foam core amp and the foam core audio system.
Nice work there! Looks like a lot of fun. I wish I could hear it in person!
I am not surprised that this systems rivals your nice tube amp - you do have a tube pre-amp to give it the "tube flavor". Have you tried it without the tube pre-amp? I don't know if you have seen my foam core class-D amp using the new Texas Instruments TPA3118D2 chip (30 watts/ch at 0.1% THD from a 4 mm x 11 mm x 1 mm high IC) but it sounds amazing compared to my stock Lepai. It even sounds better than my old Yamaha RX360 that I have put that away to make the new amp my main system amp. It will be the main one until I finish the sibling chip - the TPA3116D2 on a PCB (50 watts/ch - same form factor). The depth of the bass and clarity of the highs and how free and open it sounds is what really did it for me. More info on this amp is here in this thread: http://www.diyaudio.com/forums/class-d/219730-tpa3118d2-13.html#post3427618
I don't know if you have heard of LDR's - passive light sensitive resistors that let you control volume without any moving pots or active components to add noise. You might want to look into it for ultimate sonic purity. It will be cleaner than a tube preamp and has no amplification, but that is OK if you intend to run it between your CD player and your TA2020. http://www.diyaudio.com/forums/analog-line-level/80194-lightspeed-attenuator-new-passive-preamp.html
Here is a pic of my foam core amp and the foam core audio system.
Very cool xrk!
There is so much going on in the chip amp world. Fun stuff and very affordable!
My tube pre-amp actually has ~zero gain and it is a non-issue as my DIY DAC puts out a good, solid signal.
Before getting into any more tweaks, I am going to attempt to implement a simple rectifier so I can use the single 12vac supply for both devices and get rid of the little 12vdc supply.
There is so much going on in the chip amp world. Fun stuff and very affordable!
My tube pre-amp actually has ~zero gain and it is a non-issue as my DIY DAC puts out a good, solid signal.
Before getting into any more tweaks, I am going to attempt to implement a simple rectifier so I can use the single 12vac supply for both devices and get rid of the little 12vdc supply.
Thanks. Yes, very very affordable. My foam core amp is about $15 in parts.
You might want to use a small switch mode power supply at 12 volts. They have little noise at 60 hz (no hum) and are quite clean for powering class D amps. The noise they do have is near the switching frequency which is above audio band anyway. You can get a pretty good one on Amazon that was normally tasked to power an LCD monitor for like $7.
You might want to use a small switch mode power supply at 12 volts. They have little noise at 60 hz (no hum) and are quite clean for powering class D amps. The noise they do have is near the switching frequency which is above audio band anyway. You can get a pretty good one on Amazon that was normally tasked to power an LCD monitor for like $7.
I'd like to use a single supply for both boards. One requires 12v AC and the other requires 12v DC, so I do not think an LCD monitor supply would work for me.
The idea is to go 12vac-->preamp and 12vac-->rectifier-->amp
$22, shipping and tube included. YJ 6N3 Tube Preamplifier kit new | eBay
Listing says it is a kit, but mine arrived fully assembled. I was disappointed because I was looking forward to getting some more soldering practice.
Oh well. Not like I was going to complain about it.
Oh, also mine didn't come with the volume knob (not a fan of gold anyway), and instead of screw-terminals on the outputs it had RCA jacks (which I removed for direct soldering).
The Russian replacement tube was $1.85 plus 3 bucks shipping.
Listing says it is a kit, but mine arrived fully assembled. I was disappointed because I was looking forward to getting some more soldering practice.
Oh well. Not like I was going to complain about it.
Oh, also mine didn't come with the volume knob (not a fan of gold anyway), and instead of screw-terminals on the outputs it had RCA jacks (which I removed for direct soldering).
The Russian replacement tube was $1.85 plus 3 bucks shipping.
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Or perhaps I like second-order distortion.
But seriously, what is the source of your information on the pre-amp?
The specifications that I have access to list THD as 0.005%.
This looks like a neat product. You are not the only one who received it fully-built (others have reported as such). I think in fact it is actually always meant to be fully-built but calling it a "kit" absolves them from liability for the exposed potentially lethal HV circuitry, as there is no CE or UL approval which would make sales at reasonable prices impossible. Fine with me.
This looks like a neat product. You are not the only one who received it fully-built (others have reported as such). I think in fact it is actually always meant to be fully-built but calling it a "kit" absolves them from liability for the exposed potentially lethal HV circuitry, as there is no CE or UL approval which would make sales at reasonable prices impossible. Fine with me.
Seems reasonable.
However, they actually state outright "this is a kit,you need to solder it by yourself."
Either way, as you say, fine with me.
Costis,
You are pretty quick to dismiss something that someone else has tried and reports with first hand experience. Have you actually used or listened to the pre-amp that is being discussed, or are these opinions? Your statement that the triode is operating from 12 or 24 volts is obviously incorrect. Anyone looking at the product can see that there is a voltage multiplier present. Based on number of caps present I would say voltage 8x12 volts or 96 volts. I don't think a triode could work at 24 volts.
You are pretty quick to dismiss something that someone else has tried and reports with first hand experience. Have you actually used or listened to the pre-amp that is being discussed, or are these opinions? Your statement that the triode is operating from 12 or 24 volts is obviously incorrect. Anyone looking at the product can see that there is a voltage multiplier present. Based on number of caps present I would say voltage 8x12 volts or 96 volts. I don't think a triode could work at 24 volts.
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